The recent writing decisions are not being done by the writers during the COIE time, so what does that have to do with it? Her founding status currently also has nothing to do with poor writing decisions by itself, they'd find other ways to screw her up. Rucka established her as the third public modern superhero in his run and he did it respetfully, he didn't need to avoid putting her with Batman and Superman to do it. Swapping out one token female with another (Black Canary) and acting like there is no difference is not progressive at all, but being additive and having more than one woman would have been better. Also, as far as the very first JL stories go, she's treated better than you'd think for the time period, practically one of the guys. She fares better than the early Marvel women. So her being in the JL from the beginning was never
really a problem at all, just some forgettable stories afterward that nobody cared about.